Telkom contracts *****ing from me

I have 3 Telkom contracts , my wifi contract states I have 5 gigs daytime and 5 gigs night time data . However, after midnight , data is still being depleted from my daytime data , thus I have no access to my night data which I was promised when I signed my contract, this occurs on all my contracts . I pay for my night data every month and I signed a contract with telkom with regards to this but telkom continues to ***** from its customers. I have rebooted my modem after midnight as the consultant has said but still data is being depleted from daytime . This is Really pathetic!!!!